NYPD detectives say a gun recovered during an arrest could help solve a Bronx cold case, after forensics indicated the 380 pistol is the same gun that was used to kill an innocent 14-year-old boy on July 26, 2012, in the Baychester section.

Detectives Tom Green and Barry Sullivan described the shooting as "a gang-sanctioned hit," but added that Kemar Brooks and his friends were innocently caught up in the violence and were not the intended targets.

The shooting happened on a Thursday evening, when a severe storm caused heavy rain and knocked out power to Haffen Park.

Brooks had been a budding tennis player who spent his evenings practicing on the courts.

Detectives Green and Sullivan said Brooks and his friends ran to a gazebo for cover from the rain, not knowing the danger that lay ahead.

According to police, witnesses said the shooter entered the park through a set of stairs, entered the basketball courts and began shooting toward the gazebo where other gang members often hung out.

Brooks and his friends ran when they heard gunshots, and according to Green and Sullivan, the shooter fired again, hitting and killing Brooks.

"It's really heartbreaking to see that he really just was a kid who had no connection to any gang violence at all," Green said. "He was just a good kid. He loved the sport (of tennis), and to think that just pursuing that ended up getting him killed over some gang-related nonsense is really heartbreaking."

Brooks lived less than half a block from the park where he died.

His father found him hours after the shooting, when his son hadn't come home, his tennis rackets by his side.

"He was on his way home," the victim's father, Cassell Brooks, said fighting back tears in a 2012 interview. "My heart just fell to the ground."

Detectives Sullivan and Green said they've arrested more than 100 gang members in the neighborhood since that night and interviewed hundreds of people, in part, trying to solve this case.

The gun they recovered years later offered a potential clue, but detectives said they do not believe the man arrested with the weapon was the shooter.

"The thing is, in these gangs, the guns change hands frequently," Green said.

Sullivan added that the man they arrested with the gun "led us to other people to a point where we know what we're looking at."

Green explained they've narrowed their search to a particular gang, but they aren't yet certain who specifically pulled the trigger in Brooks' murder.

"I feel that we are going to have a successful conclusion and closure on this case," Sullivan said. "I'm confident. It might take some time, but I believe it's coming."

"We need the community to really dig deep and give us whatever they have," Green said.

Police are asking anyone with information about who killed Kemar Brooks to call Crime Stoppers at 1800-577-TIPS for a $2,500 reward.